France’s Total SA said Tuesday it would push forward with a $1 billion investment this summer in a giant Iranian gas field, the first commitment by a Western company to put real money into the Islamic Republic’s re-emerging energy industry. The Paris-based oil giant has been at the forefront of Western energy companies looking to return to Iran after sanctions on its energy industry were lifted in January 2016. Total reached a preliminary agreement late last year with China National Petroleum Corp. and an Iranian company…